Anirva sells Hair Radiance with Probiotics, a dietary supplement. This article shares research for general education and is not medical advice. These statements have not been evaluated by the Food and Drug Administration.
When more hair than usual is showing up in your brush or the shower drain, it is natural to wonder whether a vitamin might help. The short answer is that it depends on what your body is missing. Hair follicle cells divide quickly, so they need a steady supply of nutrients. When one of those nutrients runs low, hair can be one of the first places it shows. That said, the research on adding nutrients you already have enough of is still growing. So it helps to know what the studies found, and where they stop.
In this article
Key Takeaways
- Low levels matter most. Reviews of the research find the clearest links between hair and nutrients like iron, vitamin D, zinc and biotin in people who are low in them.
- Biotin is popular, but the evidence is narrow. A 2017 review found 18 reported cases where biotin helped hair or nails, and every person had an underlying condition.
- More is not always better. Too much selenium or vitamin A has been linked to hair loss, so it is worth adding up what you take from all sources.
- A simple blood test can guide you. Dermatology researchers suggest looking at diet and possible deficiencies first, when hair shedding is a concern.
Why Nutrients Matter for Hair
Hair grows slowly and steadily. MedlinePlus, from the US National Library of Medicine, notes that it takes about a month for healthy hair to grow half an inch. Shedding is part of the same cycle, because the American Academy of Dermatology says it is normal to lose 50 to 100 hairs a day.
Each hair is built by a follicle, and it depends on protein, vitamins and minerals arriving on time. This is one reason dermatologists often ask about diet when someone notices extra shedding.
Other things can cause shedding too. The American Academy of Dermatology lists childbirth, high fever, surgery, major stress and losing 20 pounds or more as common triggers. Shedding from these events usually peaks about four months later, and fullness often returns within six to nine months.
What the Research Shows, Nutrient by Nutrient
The table below brings together what reviews have found for the vitamins and minerals most often linked to hair. It also shows how much of each is in Hair Radiance, next to the Daily Value (DV) and the adult upper limit set by the National Academies.
| Nutrient | What the Research Shows | Hair Radiance (3 capsules) | Daily Value / Adult Upper Limit |
|---|---|---|---|
| Biotin | Helped hair and nails in reported cases of deficiency or specific conditions. Little evidence in people with normal levels. | 3,000 mcg | DV 30 mcg / no upper limit set |
| Iron | Low iron is common in women with hair loss. Reviews support treating a deficiency when one is found. | Not included | DV 18 mg / 45 mg |
| Vitamin D | Some studies found lower levels in people with certain kinds of shedding. Results are mixed, and trials of supplements are few. | 62.5 mcg (2,500 IU) | DV 20 mcg / 100 mcg (4,000 IU) |
| Zinc | Hair loss is a known sign of zinc deficiency. Evidence for extra zinc without a deficiency is limited. | 20 mg | DV 11 mg / 40 mg |
| Vitamin C | Helps the body make collagen and absorb iron from plant foods. | 60 mg | DV 90 mg / 2,000 mg |
| Niacin | Needed for energy use in cells. The NIH fact sheet does not list a hair effect. | 20 mg (as niacinamide) | DV 16 mg / 35 mg |
| Selenium | Supports antioxidant enzymes. Too much is linked to hair loss. | 200 mcg | DV 55 mcg / 400 mcg |
| Iodine | Needed for thyroid hormones, which play a part in the hair cycle. | 200 mcg | DV 150 mcg / 1,100 mcg |
Sources: NIH Office of Dietary Supplements fact sheets; Almohanna and colleagues, 2019; Patel and colleagues, 2017. The iron values are from the NIH iron fact sheet and are listed for comparison only.
Biotin
Biotin is the ingredient most people think of first, so it is worth being clear about what the studies show. In a 2017 review, researchers found 18 reported cases where biotin improved hair or nails. In every case, the person had an underlying condition, such as a biotin deficiency. The authors concluded there was not enough evidence to recommend biotin for healthy people. The NIH Office of Dietary Supplements agrees that claims for hair are supported by only a few case reports and small studies.
Hair Radiance contains 3,000 mcg of biotin, which is 100 times the Daily Value. There is no set upper limit for biotin, because studies have not found it to be toxic at high intakes. The main thing to know is that it can affect some lab tests (see "Good to know" below).
Iron
A 2019 review in Dermatology and Therapy noted that iron deficiency is common in women with hair loss. It suggested treating a deficiency when one is found, with enough vitamin C to help the body absorb iron. Hair Radiance does not contain iron. So if a blood test shows low iron, a doctor can suggest the right form and amount for you.
Vitamin D
Several studies have found lower vitamin D levels in people with certain types of hair shedding, compared with people without it. The same review called the results mixed, though, and said larger trials are needed to know whether supplements help. Hair Radiance has 62.5 mcg (2,500 IU) of vitamin D3, which is below the adult upper limit of 4,000 IU.
Zinc
The NIH lists hair loss among the signs of zinc deficiency. For people who are not low in zinc, the review found too little data to recommend taking more. Hair Radiance has 20 mg of zinc, which is half the adult upper limit of 40 mg.
Vitamin C
Vitamin C does not act on hair directly, as far as the research shows. It helps the body make collagen and absorb iron from plant foods, so it supports two things hair relies on. Hair Radiance has 60 mg, about two-thirds of the Daily Value.
The Main Thing the Research Agrees On
Across these reviews, one theme repeats. Nutrients make the clearest difference when someone is low in them. A 2017 review in Dermatology Practical & Conceptual recommended checking diet and possible deficiencies when someone has hair loss. It added that more research is needed to know whether supplements help when there is no deficiency. The research is still growing, and it is a helpful reason to learn your own levels.
When More Is Not Better
Because vitamins are good for us, it is easy to assume extra is always helpful. For hair, a few nutrients work the other way.
- Selenium. The NIH notes that hair loss and brittle nails are the most common signs of too much selenium. The adult upper limit is 400 mcg a day. Hair Radiance has 200 mcg, so it is worth checking other supplements for selenium too.
- Vitamin A. The 2019 review notes that taking too much vitamin A can cause hair loss. Hair Radiance does not contain vitamin A, though many multivitamins do.
- Zinc. The NIH notes that 50 mg or more of zinc a day, over weeks, can lower copper levels. Hair Radiance has 20 mg.
Vitamins Are One Part of Hair Radiance
The vitamins and minerals in Hair Radiance are at or above their Daily Values, as the table above shows. We chose each ingredient because it has been studied for hair, skin or scalp health, so readers taking Hair Radiance are not relying on vitamins alone.
The results described above come from studies of single nutrients, often in people who were low in them. They do not describe the whole formula.
Good to Know
If You Are Deciding
Dermatology researchers suggest starting with the cause. A doctor can look at your diet and history, and may check iron, vitamin D and thyroid levels. If a test shows a deficiency, treating it directly is the clearest step. Food matters too, because protein, iron and zinc come easily from a varied diet.
If you choose a supplement, give it time. Because hair grows about half an inch a month, changes in how it looks usually take a few months to show. Reading the label also helps, so you can see each amount and compare it with the Daily Value.
The Short Version
Vitamins and minerals matter for hair, and the clearest benefits show up when someone is low in them. Iron, vitamin D, zinc and biotin have the most research, though studies in people with normal levels are limited. Some nutrients, like selenium and vitamin A, can cause hair loss when taken in excess. A blood test and a look at your diet are a helpful first step, and time is part of any plan because hair grows slowly.
Frequently Asked Questions
What vitamins are good for hair growth?
Do hair growth vitamins work?
Which vitamins help with hair thickness?
Can taking too many vitamins cause hair loss?
How long do hair vitamins take to work?
Is biotin enough on its own?
References
- Almohanna HM, Ahmed AA, Tsatalis JP, Tosti A. The role of vitamins and minerals in hair loss: a review. Dermatol Ther (Heidelb). 2019;9(1):51-70. pubmed.ncbi.nlm.nih.gov DOI 10.1007/s13555-018-0278-6; PMID 30547302.
- Patel DP, Swink SM, Castelo-Soccio L. A review of the use of biotin for hair loss. Skin Appendage Disord. 2017;3(3):166-169. pubmed.ncbi.nlm.nih.gov DOI 10.1159/000462981; PMID 28879195.
- Guo EL, Katta R. Diet and hair loss: effects of nutrient deficiency and supplement use. Dermatol Pract Concept. 2017;7(1):1-10. pubmed.ncbi.nlm.nih.gov DOI 10.5826/dpc.0701a01; PMID 28243487.
- NIH Office of Dietary Supplements. Biotin: fact sheet for health professionals. ods.od.nih.gov
- NIH Office of Dietary Supplements. Vitamin D: fact sheet for health professionals. ods.od.nih.gov
- NIH Office of Dietary Supplements. Zinc: fact sheet for health professionals. ods.od.nih.gov
- NIH Office of Dietary Supplements. Selenium: fact sheet for health professionals. ods.od.nih.gov
- NIH Office of Dietary Supplements. Vitamin C, Niacin, Iodine and Iron: fact sheets for health professionals. ods.od.nih.gov
- US Food and Drug Administration. Biotin interference with troponin lab tests: safety communication (updated 2019). fda.gov
- American Academy of Dermatology. Hair shedding. aad.org
- MedlinePlus, US National Library of Medicine. Hair problems. medlineplus.gov
Hair Radiance with Probiotics
See what's actually inside the formula
Hair Radiance combines vitamins, minerals, Ayurvedic herbs and three probiotic strains in one formula, at or above the Daily Value on each nutrient shown above.
See Hair Radiance →Written by the Anirva Editorial Team | Reviewed by [REVIEWER NAME AND CREDENTIAL REQUIRED] | Last reviewed: September 25, 2026
*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
